There is no shortage of potential challengers, political watchers said this week. However, four names are on top of most lists: Colorado House Speaker Crisanta Duran, former state Sen. and gubernatorial candidate Mike Johnston, U.S. Rep. Ed Perlmutter and Gov. John Hickenlooper.

“The field is very much in flux, and there are a lot of conversations to be had,” said Craig Hughes, a Democratic campaign strategist who helped U.S. Sen. Michael Bennet win his first election in 2010. Hughes also ran Johnston’s gubernatorial bid.

The stakes are high for whichever Democrat emerges from the primary. Gardner is one of only two Republican incumbents in Senate races that Democrats will likely target as pickups. The other is U.S. Sen. Susan Collins of Maine. That means, Hughes said, the general election will be “incredibly expensive, competitive and negative.”

Let’s take a look at what each of the potential top contenders would bring to the table:

“Crisanta would be a formidable opponent for Gardner — she’s young and Latina, was extremely successful in the state Capitol, and represents a demographic he’s never been able to connect with,” said Micha Rosenoer, the executive director of Emerge Colorado, a political group that trains women to run for office.

Insiders suggested she could easily be considered the most progressive candidate of the bunch. And while that might get her through the primary, there is a question of how much appeal and name recognition she has outside of Denver, her home base.

Duran’s interest in challenging Gardner is well known in Democratic circles. However, publicly Duran is more cryptic.

“I’m currently focused on helping Governor-elect Jared Polis with his transition team and finishing up my term as Speaker,” she said in a statement. “I’m proud of the issues we’ve been able to problem solve for our state. As for my next steps, I am interested in being in a role where I can be most effective and build upon the work I’ve done but haven’t made a final decision about what that is.”

Former state Sen. Mike Johnston

Johnston came in third in the Democratic gubernatorial primary. But his campaign, which focused intensely on unaffiliated voters and took him to all 64 counties, gives him statewide name recognition among the party’s base. The former Denver lawmaker is a native son of the Rocky Mountains, which lends him credibility with voters who live in the mountains and on the Western Slope.

“He’s the kind of candidate Republicans would prefer not to face,” said independent consultant Eric Sondermann. “His challenge is going to be the Democratic primary.”

Johnston acknowledged in an interview with The Denver Post that he’s considering a run.

“A lot of folks have reached out and asked me to consider running,” he said. “I share the belief that Cory is not representing the interests of the state. … (But) I haven’t made any decision.”

Johnston added that he’ll be discussing a possible campaign with his family during the Thanksgiving holiday.

U.S. Rep. Ed Perlmutter

Perlmutter, who represents the state’s 7th Congressional District, is among the state’s most popular Democratic leaders. And the Arvada lawmaker, known for his retail politics, likely would have a lock on Colorado’s most important swing county, Jefferson, which he has represented in Congress for more than a decade.

Gov. John Hickenlooper

Don’t be fooled by the trips to Iowa and New Hampshire, Democrats have been trying to convince themselves, Hickenlooper is going to challenge Gardner in 2020. The two-term centrist governor has the record, popularity and infrastructure to easily clear the primary field and take it straight to Gardner.

While the state’s politicos might have him pegged as the man for the job, does he want it?

Nic Garcia is a political reporter for The Denver Post. He previously worked for Chalkbeat, a nonprofit news organization focused on public education, and Out Front, Colorado’s oldest LGBT news organization.

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